Yuichi Fujino

A remote surgery experiment between Japan and Thailand over Internet using a low latency CODEC system

Remote surgery is one of the most desired applications in the context of recent advanced medical technologies. For a future expansion of remote surgery, it is important to use conventional network infrastructures such as Internet. However, using such conventional network infrastructures, we are confronting time-delay problems of data transmission. In this paper, a remote surgery experiment between Japan and Thailand using a research and development Internet is presented. In the experiment, the image and audio information was transmitted by a newly developed low latency CODEC system to shorten the time-delay. By introducing the low latency CODEC system, the time-delay was shortened compared with the past remote surgery experiments despite the longer distance. We also conducted several network measurements such as a comparison between TCP/IP and UDP/IP about the control signal transmission.

Impact of network time-delay and force feedback on tele-surgery

ObjectWe have developed a robotic minimally invasive surgical system within a tele-surgery capability and conducted several times of tele-surgery experiments including Japan–Thailand and Japan–Korea tele-surgery experiments by using conventional network infrastructures. In these experiments, laparoscopic cholecystectomies have been successfully performed on pigs. On the other hand, repetitive task evaluation studies are also crucial for further studies on tele-surgery applications. Nowadays, task evaluations of tele-robotic system within network time-delay have been studied in past years by many researchers. These experiments have been mostly focused on simplified tasks such as a peg-in-hole task. However, most of surgical procedures in minimally invasive surgery are based on medical specific skills such as anatomical knowledge and past experiences of surgeons. From these perspectives, a trial experiment within two tasks including surgery oriented manipulations was conducted to study the impact of network time-delay and force feedback on tele-surgery.Materials and methodsThe experiment was conducted by using the minimally invasive surgical system. As the experimental setup, a research and development Internet, JGN2 (Japan Gigabit Network 2) was used as a network infrastructure, and two tasks were performed by 15 subjects including 5 medical doctors. The trial conditions were given by changing time-delay (on the both tasks) and force feedback (on the first task). The first task was configured to test a simple surgical procedure, which is commonly performed in a laparoscopy as translational motions of surgical tools. The subjects were instructed to touch four columns located on points of a square. The second task was configured to test integrated surgical procedures. The subjects were instructed to perform a part of suturing procedures by using the robotic bending forceps.ResultsIn the first task, the completion time was increased approximately 50% by time-delay. By using force feedback, the applied force was decreased. However, the effectiveness of force feedback was not strongly shown in MD group. On the other hand, the effectiveness of the force feedback was strongly shown in the applied force on the tip of surgical tool in both MD and non-MD groups. In the second task, the adverse impact of time-delay was not strongly shown in MD group. From the analysis of the motion records found that a skill of experienced surgeons on “occlusion problem” could be related in the results. These results indicate that skilful operators on surgical procedures can overcome the adverse impact of time-delay by introducing their skills depending on required surgical tasks. However, the drawback of time-delay still remains concerning on safety issues. The effectiveness of the force feedback was strongly shown in the first task in terms of the applied force on the surrounding environment.ConclusionsForce feedback is an essential technology for further applications of tele-surgery. In addition, the force feedback technology can be partially used for compensating the drawback of time-delay.

Tele-control of an endoscopic surgical robot system between Japan and Thailand for tele-NOTES

We describe our experience of the development of a endoscopic surgical robot system that can penetrate into the body through the esophagus and perform surgeries in the upper gastric tubes and several organs in the abdominal cavity. In this paper, we describe the results of an experiment using this robot. We describe the configuration of the control system using a gigabit ethernet system named JGN2 for the endoscopic surgical robot. We also describe the results of the first telesurgery experiment using the NOTES (natural orifice transluminal endoscopic surgery) procedure (tele-NOTES), performed at a distance of about 3,750 km.

Why does IT support enjoyment of elderly life?: case studies performed in Japan

In order to support elderly people to remain activate in communicating with their families and friends, we are developing always-on communications systems that are based on the exchange of indirect information, the videophone, and touch panel displays. Two field experiments were conducted with elderly people in Japan. One of the experiments was conducted between families members, while the other was performed between elderly people and social workers. The results show that IT can support the enjoyment of elderly life.

Communication service design by interhuman interaction approach

This paper describes a new communication service that supports all communication environments for healthy elderly people. This service was designed based on the interhuman interaction approach, and the acceptability of this system was verified by a field test.

Methods of evaluating the effectiveness of double-checking in interpreting mass screening images

In this paper we present two methods of evaluating the effectiveness of double check (by two radiologists or by a CAD system and a radiologist): One method uses ROC analysis and the other uses the phi correlation coefficient (φ). We used the first method to evaluate the effectiveness of two radiologists conducting double check through discussion (i.e. the radiologists confer; conference system). We used the second method to evaluate the effectiveness of double check in which Reader 2 makes a final assessment by referring to the assessment of Reader 1 (reference system). It is suggested that double check conducted by two radiologists through discussion may not be so effective; however, double check in which Reader 2 makes a final assessment by referring to the assessment or Reader 1 may be very effective. In addition, we discuss problems that may occur in relation to Reader 2 deciding whether to adopt the assessment of Reader 1, and practical models of double check by a CAD system and a radiologist. Continued research is necessary to establish a double check system that improves diagnostic accuracy in practical situations, i.e. it is unknown if assessments are correct.

Relationship between changes in pupil size over time and diagnostic accuracy

The objective of this study was to measure the image exploration activity of physicians, and thereby contribute to the development of a support system for CRT image interpretation in thoracic CT screening. In this study, we examined how the pupil diameters of five physicians changes over time during interpretation of a large quantity of CT images on a CRT monitor, and how this might be related to the accuracy of diagnosis. The study showed that, when a large quantity of CT images were viewed through a CRT monitor in a dimly lit room, the pupil diameter decreased during the second half of the long interpretation procedure in three of the five physicians. Furthermore, the pupil diameter frequently became approximately zero because the physician became drowsy. However, when the relationship between these phenomena and the accuracy of diagnosis was analyzed in one of the physicians, proof that such phenomena might lead to statistically significant false negatives or false positives was not found. Despite such results, the potential risk of misdiagnosis cannot be ignored. It may be necessary to devise both equipment and work conditions that will not cause the pupil diameter to become approximately zero during interpretation of images on a CRT monitor.

Network-based reading system for lung cancer screening CT

This research aims to support chest computed tomography (CT) medical checkups to decrease the death rate by lung cancer. We have developed a remote cooperative reading system for lung cancer screening over the Internet, a secure transmission function, and a cooperative reading environment. It is called the Network-based Reading System. A telemedicine system involves many issues, such as network costs and data security if we use it over the Internet, which is an open network. In Japan, broadband access is widespread and its cost is the lowest in the world. We developed our system considering human machine interface and security. It consists of data entry terminals, a database server, a computer aided diagnosis (CAD) system, and some reading terminals. It uses a secure Digital Imaging and Communication in Medicine (DICOM) encrypting method and Public Key Infrastructure (PKI) based secure DICOM image data distribution. We carried out an experimental trial over the Japan Gigabit Network (JGN), which is the testbed for the Japanese next-generation network, and conducted verification experiments of secure screening image distribution, some kinds of data addition, and remote cooperative reading. We found that network bandwidth of about 1.5 Mbps enabled distribution of screening images and cooperative reading and that the encryption and image distribution methods we proposed were applicable to the encryption and distribution of general DICOM images via the Internet.